There is an old joke about acceptance of homosexuality that ends with the punchline: ‘Well it’s alright as long as they don’t make it compulsory.’ The gag is ubiquitous, but resonates with Australians because it reflects the larrikin wit imbued in our national character.

Now, no one is laughing. Those who thought the anecdote amusing have been silenced by the realisation that the joke is on them, as the punchline is close to becoming a reality. To top it off, those not amused or even mildly affronted have the growing support of the politically correct to seek redress through various quasi-legal bodies with power to silence or censor naysayers. That is enough to wipe the smile from anyone’s face.

Look no further than Exhibit A, the senseless push by the social engineers and activists who see some public benefit in same-sex marriage.

As indicated in the anecdote, most Australians are tolerant or accepting of homosexual relationships. In addition, legislation that discriminated against same-sex couples has been all but purged from the statutes — as it should be. So why has gay marriage become the cause célèbre of the elites and the non-thinking Left when there are no victims or oppression, just a desire by a group of people to have something which nature dictates they have no entitlement — or equipment?

Champions of social justice such as the Age have been hectoring non-believers, stopping just short of accusing Australians of swimming in a social backwater of bigotry, intolerance and homophobia. They foster the impression that same-sex marriage is a bold step that will somehow redefine Australia as a nation.

If it does, it will not be for the better. Such defining moments are created through events that shape our history and our national psyche, as well as our achievements in science, medicine and the arts. Sexual preference does not, and should not, get a look in.

Spurred by the substantial conscience vote in the British House of Commons in favour of legalising gay marriage, and a similar vote in France, the Age went on the attack last week. ‘Australia’s Federal Parliament may be half a world away from the Palace of Westminster, but as far as same-sex marriage is concerned it might as well be in another universe,’ it thundered. ‘The debate and the fight for equal rights for gays will continue — and, indeed, intensify, especially in an election year. The more democracies that endorse gay marriage, the more isolated and out of touch with reality Australia will become. It is time we entered the modern world.’

More urging came from the sidelines via the Sydney Morning Herald’s Peter Fitz-Simons, a former rugby player who had a brief career in the Wallabies and has an even more brief acquaintance with geopolitics. FitzSimons believes Gillard should embrace gay marriage, metaphorically speaking. ‘Yes, the PM has opposed it, but so did Obama, before having his position “evolve”. So must hers,’ he wrote in a Sunday column. ‘When even the British Conservatives can embrace sanity and thumpingly endorse gay marriage as they did this week, how can the ALP possibly position themselves as the party of progressive change and still be against it?’

Really? It is time the whistle was blown on this falsehood. By all means allow some form of legal union among same-sex couples. However, it cannot be called marriage nor carry the same privileges or benefits. Forgotten in this debate is the fact that the Marriage Act does not discriminate against homosexuals as much as their own sexual orientation. Under the act, marriage is the union of a man and a woman with the specific aim of procreation and creating a supportive, nurturing, long-term family environment for the offspring.

Simply put, the gender of same-sex couples precludes coverage by the Marriage Act; nor should the nature of the act be changed to include them. To do so risks a politically correct unravelling of the very fabric of our society.

The problem is caused by the desire of same-sex couples to have children, despite their fundamental lack as a unit of what is required.

The issue of adoption by same-sex couples is already covered in various pieces of state legislation, although debate on the issue is far from settled. Even more contentious issues revolve around in vitro fertilisation treatments and surrogacy if same-sex marriage becomes legal.

IVF was a breakthrough treatment to enable infertile couples to have children. However, since January 2010, Medicare rebates for treatment have been extended to single women and lesbians. The moral dilemma here is brought into sharp focus if lesbians attain marital status. Should fertile women, who choose not to enter a heterosexual relationship, be afforded the same status in the program as infertile couples? If the answer is yes, does this amount to discrimination against heterosexuals?

Surrogacy poses legal as well as moral and ethical issues. There is no question that same-sex marriage would heighten calls for the legislation of commercial surrogacy, even though altruistic surrogacy — where no money changes hands — is legal in all states. Undoubtedly such moves would be supported by the Left, which in a masterful paradox is predominantly pro-abortion.

Legal parenthood also comes under the spotlight. What details go on a birth certificate? In a bizarre case in Florida last week, a county court judge determined that 23-month-old Emma Filippazzo would have three parents named on her birth certificate: a lesbian couple and a homosexual man.

If this is the modern world, let us linger in our backwater.

When activists first mounted street marches in the 1970s, as noted by Brendan O’Neill in the Australian, the mantra was anti-marriage, as it was deemed by homosexuals to be a ‘rotten, oppressive institution’. It is odd that now as the crude marriage rate in Australia is falling (it went from 6.9 registered marriages per 1,000 estimated resident population in 1990 to 5.4 in 2010), that same-sex marriage is being billed as the last frontier of gay rights.

This points to an alternative agenda which might be more in tune with the radical ideals of the 1970s. There can be no doubt legalised same-sex marriage would weaken the influence of Australia’s major institutions, and in particular the Catholic Church, which tops the list of targets for any anti-establishment group. The latte set — as usual — has fallen for it.

Ian Moore is a former editor of the Sunday Telegraph and the founding editor of the Sunday Herald Sun.